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991.
Li-ion rechargeable batteries based on polymer electrolytes are of great interest for solid state electrochemical devices
nowadays. Many studies have been carried out to improve the ionic conductivity of polymer electrolytes, which include polymer
blending, incorporating plasticizers and filler additives in the electrolyte systems. This paper describes the effects of
incorporating nano-sized MnO2 filler on the ionic conductivity enhancement of a plasticized polymer blend PMMA–PEO–LiClO4–EC electrolyte system. The maximum conductivity achieved is within the range of 10−3 S cm−1 by optimizing the composition of the polymers, salts, plasticizer, and filler. The temperature dependence of the polymer
conductivity obeys the VTF relationship. DSC and XRD studies are carried out to clarify the complex formation between the
polymers, salts, and plasticizer. 相似文献
992.
Lu Wang Meicheng Li Wenxin Wang Haitao Tian Zhigang Xing Min Xiong Liancheng Zhao 《Applied Physics A: Materials Science & Processing》2011,104(2):567-572
The effect of strain accumulation in the InAs/In
x
Ga1−x
As quantum dots (QDs) system was studied in this work. It was found that strain in the In
x
Ga1−x
As layer accumulation in the QD layer. This effect resulted in a dramatic reduction of growth mode transition thickness of
the QD layer. For InAs/In0.25Ga0.75As QDs, critical thickness is measured to be as low as 1.08 ML. The experimental results in this work highlight the importance
of strain accumulation in the design and fabrication of QD-based devices with metamorphic buffer layer involved. 相似文献
993.
Min Hwan Lee Kyung Min Kim Seul Ji Song Sang Ho Rha Jun Yeong Seok Ji Sim Jung Gun Hwan Kim Jung Ho Yoon Cheol Seong Hwang 《Applied Physics A: Materials Science & Processing》2011,102(4):827-834
The bipolar resistive switching mechanisms of a p-type NiO film and n-type TiO2 film were examined using local probe-based measurements. Scanning probe-based current–voltage (I–V) sweeps and surface potential/current maps obtained after the application of dc bias suggested that resistive switching is
caused mainly by the surface redox reactions involving oxygen ions at the tip/oxide interface. This explanation can be applied
generally to both p-type and n-type conducting resistive switching films. The contribution of oxygen migration to resistive
switching was also observed indirectly, but only in the cases where the tip was in (quasi-) Ohmic contact with the oxide. 相似文献
994.
在NaSh模型的基础上,考虑交通事故和养护路段等意外事件对高速公路交通流的影响,建立了有意外事件影响的在车道管制下的高速公路交通流元胞自动机模型,并进行数值模拟. 研究发现:意外事件对高速公路交通流有明显影响,并且意外事件对交通流的影响在某一密度值范围内尤其明显,且意外事件堵塞点在第一车道比在第二车道对交通流的影响小;同时,在该密度值范围内,意外事件堵塞时间和堵塞路段长度越长,对交通流的影响就越大.
关键词:
元胞自动机
交通流
意外事件 相似文献
995.
996.
The crystal structure, magnetism properties, and density of states for FeAs layered compound SrFe2As2 have been investigated by using the density functional theory (DFT) method. The magnetism under a checkerboard nearest neighbor anti-ferromagnetic (NN AFM) and ferromagnetic (FM) order ground-state have been analyzed with substitution for Sr with K ion in Sr1−xKxFe2As2. The results indicate that the distortion of FeAs tetrahedrons is sensitive to the electron doping concentration. The system magnetism was suppressed by K doping in NN-AFM ground state instead of FM. The density of states at Fermi level N(EF) under NN AFM ground state would be regarded as a driving force for the increased Tc of Sr1−xKxFe2As2 system as observed experimentally. Our calculation reflects that NN AFM type spin fluctuation may still exist in the Sr1−xKxFe2As2 system and it may be an origin of strong spin fluctuation in this system besides the spin density wave (SDW) states. 相似文献
997.
"Rainbow trapping" has been proposed as a scheme for localized storage of broadband electromagnetic radiation in metamaterials and plasmonic heterostructures. Here, we articulate the dispersion and power flow characteristics of rainbow trapping structures, and show that tapered waveguide structures composed of dielectric core and metal cladding are best suited for light trapping. A metal-insulator-metal taper acts as a cascade of optical cavities with different resonant frequencies, exhibiting a large quality factor and small effective volume comparable to conventional plasmonic resonators. 相似文献
998.
Samuel BeckfordNicholas Langston Min Zou Ronghua Wei 《Applied Surface Science》2011,257(13):5688-5693
Low surface energy polymer thin-films can be applied to surfaces to increase hydrophobicity and reduce friction for a variety of applications. However, wear of these thin films, resulting from repetitive rubbing against another surface, is of great concern. In this study, we show that highly hydrophobic surfaces with persistent abrasion resistance can be fabricated by depositing fluorinated carbon thin films on sandblasted glass surfaces. In our study, fluorinated carbon thin films were deposited on sandblasted and as-received smooth glass using deep reactive ion etching equipment by only activating the passivation step. The surfaces of the samples were then rubbed with FibrMet abrasive papers in a reciprocating motion using an automatic friction abrasion analyzer. During the rubbing, the static and kinetic friction forces were also measured. The surface wetting properties were then characterized using a video-based contact angle measuring system to determine the changes in water contact angle as a result of rubbing. Assessment of the wear properties of the thin films was based on the changes in the water contact angles of the coated surfaces after repetitive rubbing. It was found that, for sandblasted glass coated with fluorinated carbon film, the water contact angle remained constant throughout the entire rubbing process, contrary to the smooth glass coated with fluorinated carbon film which showed a drastic decrease in water contact angle with the increasing number of rubbing cycles. In addition, the static and kinetic friction coefficients of the sandblasted glass were also much lower than those of the smooth glass. 相似文献
999.
Min FangHaiping He Bin LuWeiguang Zhang Binghui ZhaoZhizhen Ye Jingyun Huang 《Applied Surface Science》2011,257(20):8330-8333
We report the structural and optical properties of copper aluminium oxide (CuAlO2) thin films, which were prepared on c-plane sapphire substrates by the radio frequency magnetron sputtering method. X-ray photoelectron spectroscopy (XPS) along with X-ray diffraction (XRD) analysis confirms that the films consist of delafossite CuAlO2 phase only. The optical absorption studies show the indirect and direct bandgap is 1.8 eV and 3.45 eV, respectively. Room temperature photoluminescence (PL) measurements show three emission peaks at 360 nm (3.45 eV), 470 nm (2.63 eV) and 590 nm (2.1 eV). The first one is near band edge emission while the other two are originated from defects. 相似文献
1000.
Qiumin Yang Jie Zhao Min Guan Chao Liu Lijie Cui Dejun HanYiping Zeng 《Applied Surface Science》2011,257(21):9038-9043
CdSe thin films have been grown on GaAs (0 0 1) substrates by molecular beam epitaxy (MBE). The effects of substrate temperature and annealing treatment on the structural properties of CdSe layers were investigated. The growth rate slightly decreases due to the accelerated desorption of Cd from CdSe surface with an increase in the temperature. The sample grown at 260 °C shows a polycrystalline structure with rough surface. As the temperature increases over 300 °C, crystalline CdSe (0 0 1) epilayers with zinc-blende structure are achieved and the structural quality is improved remarkably. The epilayer grown at 340 °C displays the narrowest full-width at half-maximum (FWHM) from (0 0 4) reflection in double-crystal X-ray rocking curve (DCXRC) and the smallest root-mean-square (RMS) roughness of 0.816 nm. Additionally, samples fabricated at 320 °C were annealed in air for 30 min to study the films’ thermal stability. X-ray diffraction (XRD) results indicate that the zinc-blende structure remains unchanged when the annealing temperature is elevated to 460 °C, meaning a good thermal stability of the cubic CdSe epilayers. 相似文献